Plate for artificial teeth



UNITED l STATES. PATENT OFFICE.

MAHLON LOOMIS, OF CAMBRIDGEPORT, MASSACHUSETTS.

PLATE FOR ARTIFICIAL TEETI-I.

l Specification of Letters Patent No. 10,847, dated May 2, 1854.

To all 'whom t may concern.'

Be it known t-hat I, MAHLoN LooMrs, of Cambridgeport, in the county ofMiddlesex and State of Massachusetts, have invented a new and usefulImprovement in the Manufacture of Artificial Teeth; and I do herebytions of such half sets. Fig. 5, is a top view of the half mold of theupper jaw, the same exhibiting by the colored portion, a., the amounto-f enlargement for shrinkage of the porcelaimas hereinbefore described.Fig. 6,

is a similar view of the ylower part of the mold for the lower jaw set,and shows the process of enlargement for such purpose, 1t being effectedby sawing the mold longitudi nally and transversely into four pieces,5,0,

V d, e, and extending them apart and inserting strips of wood, f, g,between them.

My invention consists in making whole sets or the upper or lower halvesor parts of sets of artificial teeth all of porcelain. A half setconsists of but one piece of material,

` there being no metallic plate, as in the usual way, but the samematerial of which the teeth themselves are made is used instead of ametallic plate. A.

To make a full set of artificial teeth, thin silver plated or otherproper metallic plates are first to be accurately fitted to the upperand lower jaws in order that the exact size and shape of that part ofthe mouth to be fitted maybe definitely known. These plates are to bemade by the ordinary process of gold plates, to which sets of teethareusually fastened. Vax is next to be placed upon these plates in order todetermine somewhat the lengt-h and position of the teeth to be made.Next the inside of the plate or that side which is `applied to the flesho-f the mouth is to be filled and covered over with dentists plaster(wet to a convenient consistence) and said plate with the plaster is tobe placed upon a thin bed of the same plaster, so that `the plaster onthe plate shall rest on the bed of plaster. To prevent the bed ofplaster from spreading and the better to shape it, it may be confined bymeans of a measurement and experiment.

strip of sheet iron about'an inch in width bent somewhat in the form ofthe letter U and continued straight across so that the ends may toucheach other. Vhenthis bed of plaster has become sufliciently hardened,the sheet iron or metallic form last men tionedis to be removed. Themetallic plate is next to be taken off from the whole of the plaster.The plaster after this may be neatly trimmed. When this plaster cast,upon which is to be formed the upper half of the set of teeth, is to beenlarged to coun teract in part the effect of the shrinkage of theporcelain material consequent upon baking such may be effected asfollows: As different mixtures for porcelain differ in the amount theycontract by baking, theextent of enlargement (as near as I can estimatethis enlargement I should say that generallyy speaking it would increaseeach of the dimensions of the mold one sixteenth of it) must be inproportion to the amount of shrinkage, which may be` ascertained by Thisascertained the aforesaid plaster cast, upon which is to be formed thehalf set or that portion for the upper jaw, may be scooped out suflif4ciently to allow for shrinkage; and it may be extended back orlengthened the proportional distance from the mark left by the rear edgeor limit of the plate and so as to allow for the longitudinal shrinkage.When the enlargement of the plaster cast has been completed, the waxwhich was before placed on the metallic plate is to be removed therefromand placed on the plaster cast, the deficiency at'its two extremitiesbeing supplied if necessary, its height and breadth corrected `(ifrequisite) by `the addition of other portions of wax; This wax so put onthe cast is designed to form aspace between the two pieces of plasterwhich are to compose the matrix for forming the porcelain material 0fthe teeth. After the wax has been thus adjusted, it may be oiled inorder that prepared plaster, which is next to be poured or placed uponand over both the wax and remaining surface of the lplaster cast uponwhich it is placed, may be subsequently the more easily separated fromsaid wax and plaster which` separation is to l be eected when thisplaster last `used has become hard or set. This plaster last put on isfor the purpose of forming the other portion of the matrix. Next asuflicient portion of the plaster so removed must be cut away from t-hewhole mass in order to make, when the two parts of the mold are placed1n contact, a space which will admit of the porceing the mass of plasterapart crosswise and next glueing the parts firmly together with a pieceof wood between them, such pieces of wood to correspond in thicknesswith the y amount of shrinkage of the porcelain material, in alongitudinal direction. Next the whole may be again cut apart at rightangles with the first separation and again glued together, with asimilar strip of wood between the two halves, such strip allowing forthe l transverse shrinkage.

Now the inferior or last made half of each of these matrices may bespaced ofi' upon the edge, which determines the outer surface of theporcelain vmaterial, and so as to determine the width and positionsofthe teeth to be made. First, that for the upper teeth is spaced tosuit the occasion. Then to space that, for the lower teeth, the flatsides of the two may be placed togethenand that for the lower teethspaced by marking between the spaces Aof that for the upper teeth. `Thenafter thinly coating with bayberry tallow that surface of the matrixwhich is a representation of the part of thevmouth to be fitted it isready to receive the lporcelain material, which may c next be carved orshaped as may be necessary. This being done, the mass of porcelainmaterial may be warmed until it melts the tallow beneath, so as to admitof its being removed from the matrix. Thile in this condition anydesirable shape may be given to its edges of the part so formed in thematrix by applying where desired a thinly v diluted portion of theporcelain mixture by meansI of a small camels hair pencil. Next the castis to be placed upon the tile for baking it in the usual way aspractised in manufacturing porcelain. After the two portions have beentaken from the furnace the last time they may be ground on their insidesurfaces where they may need it in order to make them fit accurately aplaster bed or perfect representation of that part of the mouth which itis desired to fit.

When the mouth to be fitted with teeth is of such a peculiar shapeas torender it a difiicult operation to remove the carved work from thematrix, which faithfully represents it, as it sometimes the case withthe upper jaw, the difficulty may be obviated in the following manner:After the metallic plate has been accurately fitted to the mouth,

itr may be taken and oiled on its inside surface. Next, with dentistsplaster moistened to a convenientconsistence, such portions of the oiledsurface of the plate may be covered as shall most seem to interfere withits direct removal from the hardened mass of paster, which is afterwardmade to fill it,'and it is well to divide into small separate piecesthat plaster which is thus first placed in the plate in order that itmay be subsequently more easily removed from the work, which is to beshapedv and carved upon it. Next, when these plaster pieces have becomehard, their outer surface should be thinly covered with bayberry tallowor its equivalent. The remaining portion of the oiled surface of theplate is next filled and covered over with a similar preparation o-fplaster. Vhen this becomes hard, it is also to be covered with bayberrytallow or the equivalent and the t-allowed surface placed upon a thinbed of prepared plaster confined to its place by means of a sheetironform, as before spoken of. The plate may neXt be removed and the moldenlarged and nished in the same way as the matrix before described.

Some o-f the advantages of making sets of teeth in my way are quiteapparent, for a half set thus all solid and in one piece of materialwill be in use a cleaner and purer job than those made in the usual way,(viz, of gold metallic plate and teeth fitted thereto,) there being nojoints around the teeth made after my plan for the accumulation offoreign substances. They can also be afforded at an incomparably lowervprice than those as usually made, thus extending the benefits ofartificial teeth to hundreds o-f persons who cannot afford them on goldor platina plates.

In actual practice I find -it is much easier to make teeth in this way,my method proving to be a great saving of time and labor. I havel fittedseveral jaws, both upper and lower, with sets of teeth made on myAimproved plan, which teeth are now in daily use, answering everyrequirement.

I do not claim the'process above set forth. In making sets of artificialteeth I do not claim the spreading of a gum enamel over one side of ametallic roof plate upon which the teeth are fastened, nor the extensionof the porcelain gum some wayV and not en# tirely upon the roof, but

What I claim as my invention is- The improved manufacture of whole orhalf sets of porcelain or mineral teeth substantially as described.

In testimony whereof I have hereto Set l my signature this twenty-sixthday of October A. D. 1853. MAI-ILDN LOOMIS. Witnesses:

R. I-I. EDDY, F. P. HALE, Jr.

